off the rails

Abnormal or malfunctioning condition
Off the rails is an idiom that means in an abnormal or malfunctioning condition, especially in a way that causes damage or disorder. It can also refer to a train that leaves its rails during movement, or to the carom of a pool ball with the rail.

***
go off the rails
idiom
informal
: to lose control and start to behave in a way that is not normal or acceptable
He was a promising student but he went off the rails after he started taking drugs.

Examples of go off the rails in a Sentence

Sony Pictures Things go off the rails a bit with Spider-Man 3, which is a bit overstuffed in, well, just about every way.
—Evan Romano, Men's Health, 2 June 2023
Gaughan had an acute sense that such a major case could, without careful tending, go off the rails at any moment, McMahon said.
—Megan Crepeau, Chicago Tribune, 27 Nov. 2022
Making seasonal deals available weeks or months before Black Friday can ease some of the pressure and reduce the likelihood that anything will go off the rails.
—Gary Drenik, Forbes, 17 Aug. 2022
Ivan Perez, 53, is philosophical about what caused his life to go off the rails.
—New York Times, 18 Apr. 2022
Once the livestreams roll, though, things can quickly go off the rails, and often do.
—Cecilia D'anastasio, Wired, 12 Jan. 2021
Any moment can go off the rails and become a Saturday Night Live sketch.
—Brian Davids, The Hollywood Reporter, 24 May 2023
Democrats remember all too well how badly an agenda can go off the rails when Congress breaks for summer recess with big questions looming.
—Philip Elliott, Time, 16 June 2021
Solos needed more eloquence, there were intonation issues and faster passages sometimes threatened to go off the rails.
—Tim Diovanni, Dallas News, 13 June 2021

***
train wreck

NOUN
trainwreck (noun)
a collision or other accident involving a train:
"a relative was killed in the Humber river train wreck"
NORTH AMERICAN ENGLISH
informal
a chaotic or disastrous situation that holds a peculiar fascination for observers:
"his train wreck of a private life guaranteed front-page treatment"

Translate train wreck to German

noun
Zugungl;ck
Zugwrack

***
train wreck
noun [ C usually singular ] mainly US informal

something that fails completely or goes extremely badly:
The movie was a train wreck.
After last year's train wreck of a season, we have to do better.
Synonyms
car crash
dumpster fire US
 SMART Vocabulary: related words and phrases
Failures
another/the final nail in the coffin idiom
bloodbath

breakdown
busted
flushcar
crashfoul (something)
up free fall
game over idiom
hash
lemon
lost cause
lulu
mess
nail
reversal
slim pickings
slush
pile track record
turkey

train-wreck
adjective [ before noun ] mainly US informal

failing completely or going extremely badly:
It's train-wreck television - so bad it's almost fascinating.
It is a train-wreck political strategy and political consequences will be inevitable.
 More examples
 SMART Vocabulary: related words and phrases
(Definition of train wreck from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
EXAMPLES of train wreck
train wreck
Her train wreck dating life is a constant joke among her friends, as she is seen dating someone new every week.
From Wikipedia
Seconds later, a massive train wreck occurs, keeping his wife there.
From Wikipedia
If the uncontrolled rolling stock derails or hits another train, a train wreck may result.
From Wikipedia
If the player rolled "all" five cubes and scores no points, this is a train wreck.
From Wikipedia
They worried that a telegraph mix-up might result in a train wreck.
From Wikipedia
He claims that he was in a train wreck.
From Wikipedia
He later seemingly disappeared completely, leading to widespread rumors that he had died in a train wreck.
From Wikipedia
The tracks get rearranged, leading to an impending train wreck.
From Wikipedia
Services were held five days after the train wreck.
From Wikipedia
In 1900, a washout during a thunderstorm caused a train wreck about 1 miles (2.4 km) north of town.
From Wikipedia
Meanwhile, his new bride was in a train wreck and subsequently had to use a wheelchair, after which she took up the art of painting.
From Wikipedia
In 1953, a train wreck destroyed the town depot, and no new one is forthcoming.
From Wikipedia
But otherwise, avoid this train wreck at all costs.
From Wikipedia
Unlike some other songs in the train wreck sub-genre, it is not based on a real incident, and it does have a known author.
From Wikipedia
They both survive the train wreck, only to vanish, and reappear as the undead stars of a dual boss-battle, mocked up as a ballet performance.
From Wikipedia